Alzheimer's disease disrupts arithmetic fact retrieval processes but not arithmetic strategy selection

Area of Science:

• Cognitive Neuroscience
• Neuropsychology
• Gerontology

Background:

• Aging affects cognitive functions, including arithmetic processing.
• Alzheimer's disease (AD) is associated with significant cognitive decline.
• Understanding specific cognitive deficits in AD is crucial for early detection and intervention.

Purpose of the Study:

• To investigate arithmetic fact retrieval and strategy selection in healthy younger adults, healthy older adults, and patients with probable AD.
• To determine if age-related changes in arithmetic processing differ from those seen in early AD.
• To explore the impact of problem characteristics on strategy use in these groups.

Main Methods:

• Participants performed an addition/number comparison task involving 128 problem pairs.
• Problem difficulty and numerical characteristics were manipulated to assess strategy selection.
• Performance was analyzed for arithmetic fact retrieval accuracy and strategy switching capabilities.

Main Results:

• Arithmetic fact retrieval processes were impaired in probable AD patients.
• These retrieval processes were preserved in healthy older adults compared to younger adults.
• AD patients demonstrated strategy switching abilities, though less systematically than younger adults and similar to older adults.

Conclusions:

• Arithmetic fact retrieval is specifically impaired in Alzheimer's disease, beyond typical aging effects.
• Problem-solving flexibility, indicated by strategy switching, is relatively preserved in early AD.
• Findings highlight distinct cognitive profiles in aging and AD, with implications for understanding general problem-solving deficits.